Improvement in processes of burning pottery-ware



UNITED STATES PATENT OFFICE.

GEORGE O. HICKS, OF BALTIMORE, MARYLAND.

IMPROVEMENTIN PROCESSES OF BURNING POTTERY-WARE, &c.

Specification forming part of Letters Patent No. 125,048, dated March26, 1872; antedated March 12,1872.

To all whom it may concern:

Be it known that I, GEORGE O. HICKS, of the city and county of Baltimore and State of of Maryland, have invented certain Improvements in Kilns for Burning PotteryJVare, Galcining Lime, and similar purposes; and I hereby declare that the following is afull, clear, and exact description thereof, reference being had to the accompanying drawing, which represents a vertical longitudinal section of such kiln.

111 the ordinary process of burning such wares the oxygen necessary for combustion has afree entrance, and the products thereof a free exit from the oven or kiln, thus creating a current of heated air therethrough. The consequence is that all wares deposited are heated to a hi gher degree and much quicker on the side toward the fire than on the opposite one; this causes considerable loss by the uneven expansion of the material, resulting in its cracking or distortion of form. In an open kiln, also, a large percentage of caloric passes oh, and a long time and great consumption of fuel is necessary to accomplish the desired result.

To economize fuel, produce a higher temperature, uniformity and rapidity of burning, and consequent saving of a large portion, if not all, of the ordinary waste from cracking or other imperfections of the ware under treatment, is the object of my invention; and it consists in constructing a closed kiln and supplying the fire-chamber with oxygen for combustion by a forced blast, which, together with its expansion in the kill, shall cause a uniform temperature and pressure on all sides of the article to be burned.

For the better understanding of my invention, I will refer to the accompanying drawing, in which A represents the compartment or oven in which the pottery or other articles to be burned are deposited, and B the fuelehamber, each provided with aremovable end,

0 O, which are connected, to close said chambers by lugs and saddle-bars, similar to the man-hole cover of a steam-boiler or gasretort. This kiln and fuel-chamber may be of any convenient form, but I prefer cylindrical, on account of strength and cheapness. They are made of boiler iron, lined with fire-brick, and between the iron and brick a filling of any suitable refractory material in a pulverized state.

The kiln being charged and the fire-ch amber filled with fuel, of which any kind may be used, the ends 0 O are to be closed, and, after ignitin g the fuel, a blast of air is then forced through the tube D, to supply oxygen to support combustion, said blast being maintained to any desired pressure within the kiln according to the nature and qualityof the material to be burned,

such pressure and consequent heat hein g controlled by the weighted valve E on the top of the kiln. In the tube D may also be provided a pressure-gauge, G, which, being arranged beneath the fire-chamber, will not be subject to the efi'ect of the heat therefrom. A peep or sight tube, E, and lens may also be inserted in the end or in any convenient part of the kiln, through which to inspect the progress of the operation.

Having thus described my invention and the apparatus for operating it, what I claim, and desire to secure by Letters Patent, is-

1. The process of burning potteryware or calcining lime in a closed kiln, substantially as herein described.

2. Akiln, constructed essentially as set forth, for the purposespecifiedf 3. In combination with such kiln, I claim the arrangement of the blast-pipe and pressure-indicator beneath the fuel-chamb er or kiln, for the purpose set forth.

GEORGE O. HICKS.

Witnesses:

SYDNEY E. SMITH, W. Monnrs SMITH. 

